Front brakes... What to do..

[ChilliWhizz]

Went for a HiSpec front brake conversion in 2013, 300mm rotors and 4 pot calipers. Brilliant initially then developed horrendous judder. Investigation showed rotors had warped, so had them skimmed on the car. Brilliant again, then last year got the judder back, which has got progressively worse...

So, what are my options... I intend to get Mat Smith to check everything over on the front, but TBH I've lost confidence in the set-up. Assuming it is the brakes that are causing the judder, I could take the car down to HiSpec and ask them to investigate/remedy (leaving aside any responsibility issues for the sake of this post), or, look at sourcing replacement discs and bells that would be compatible, retaining the HiSpec calipers, or, change the set up completely, like maybe the E38 discs and Brembo calipers..

Thoughts and opinions sought!!

Thanks chaps,

Chilli

[griffdude]

Were they 1 piece discs? If so it might be worth a call to hispec as they sell 2 piece ones for a reasonable price.
http://www.hispecrotors.co.uk/

[Alexdaredevils]

Keep with what you've got and sort them out

[portzi]

What brand of disc did you go for? I have the AP caliper on my chim and within 12 months my discs warped. So skimmed them and within 6 months they warped again. Bit the bullet and spent double the amount of originals and bought some bosch disks, l use disks originally designed for a jeep cherokee as cerbera disks are £100 a pop. Bosch cherokee ones are £50 each. Well 18 months on no problems. What l am saying in buying a cheaper disc has cost me more in the longrun. . Lessons learned.

[phazed]

I used to run Brembo discs on my 4.6 with 4 pot Bremsport calipers, never had a problem.

[brett84]

I've got the e38 callipers with RS Focus discs (324mm) with Mintex M1144 pads
They are very sharp, great pedal feel. Took some getting used to so they don't keep locking up thought compared to what I had before.
Much cheaper kit than anything else I could find, you get a huge choice of Pads and discs because you're using ford/BMW parts

[ChilliWhizz]

Guys, I bought the complete HiSpec conversion kit so all HiSpec components... piccie below (hopefully)

[Andav469]

have you checked for any 'run out' when the discs are fitted, if they are not within tolerance then they will flatspot and give the same symptom as warped discs

[ChilliWhizz]

Hi Dave, it was checked at Mat Smiths when the discs were skimmed....

[Brummmie]

I'd try a decent pad before anything else.

[ChilliWhizz]

I'm using Ferodo DS2500's Brummmie...

[rigga]

Were the hub faces meticulously clean before fitting the discs?

[BarnFind]

Andav469 said:

have you checked for any 'run out' when the discs are fitted, if they are not within tolerance then they will flatspot and give the same symptom as warped discs

What does this mean ?

[Andav469]

BarnFind said:

What does this mean ?

If the discs are out of true (maybe dirt/rust on the hub mating face) then the caliper will wear harder on one area of the disc and cause vibration

[QBee]

If you are thinking of a disk change talk to Mat about Black Diamond disks. I have them all round on my car, fitted by him on his recommendation. Mine are 324mm front and 273mm rear and I have had no problems with them. Awesome stopping power, they are grooved but not drilled.

ETA Demon Tweaks sell them 25mm thick for £110 a pair in 300mm

http://www.demon-tweeks.co.uk/performance/brake-di...

Edited by QBee on Wednesday 4th February 21:27

[Brummmie]

rigga said:

Were the hub faces meticulously clean before fitting the discs?

People don't realise how important this is, any rust or dirt will cause run out.
And ds2500 are a reasonably good pad.

[s p a c e m a n]

I've been searching for half an hour and can't find the thread that I read recently on here about a dodgy pair of brake discs, but what it came down to was that someone had upgraded their brakes and ended up with an exceptionally soft pair of discs. They are after all just a manufactured product so there is always a possibility of a defect in the process.

If you can find nothing wrong with the fitment and have just skimmed the discs rather than changing them then I can only suggest swapping them for another pair, I would try a different brand though.

[ChilliWhizz]

rigga said:

Were the hub faces meticulously clean before fitting the discs?

Good question rigga Questionable on the original fitment, however, prior to skimming, all components and in particular the hub faces were meticulously cleaned. Following this the brake performance was as expected, and no hint of judder... same as the first attempt. Must have been a couple of thousand miles and a few months later that the judder/vibration/shaky steering wheel syndrome returned.. and proceeded to get progressively worse..

I've sent HiSpec an email describing the problems to see if they have any ideas (like maybe others have had similar problems around the same time - bad batch or something) but no reply yet...

Chilli

[ChilliWhizz]

QBee and spaceman, thanks for the suggestions fellas. When I speak to Mat I'll ask him about the BD discs. What I don't know is if another brand of disc would bolt straight on to the HiSpec bell's, or if I'd have to buy bells to go with the new discs, and the obvious one would the discs be centralized in the calipers... I'm a bit nervous when it comes to mix and match with brake components (often for no good reason), but the idea of having bespoke adaptor brackets made to line up rotors and calipers doesn't give me a warm fuzzy feeling...

[Pupp]

You sure it's not material being deposited on the rotors from the pads? Can happen if/when you sit on the brakes when stationary right after hard use... Happens more often than warping in my experience